Thanks for the heads up. Would I need to withdraw them from an exchane like coinbase snd transfer to my blockchain wallet?
The idea is to collect your coins from any places where you don't control the private keys, to wallets where you do.
There are some wallet suggestions at
https://bitcoin.org/en/choose-your-walletWhen you click on one, you can see whether it allows you to control your own coins. Some wallets have a green dot next to "Control over your money" and if you click that, it shows "This wallet gives you full control over your bitcoins. This means no third party can freeze or lose your funds. You are however still responsible for securing and backing up your wallet."
When you hold your own coins yourself, you have to protect them from hackers and make sure you have backups. A hardware wallet can help in case your PC gets hacked.
The advantage is that you actually have your coins. Maybe your coins are held today by the next mtgox disaster. Maybe they already lost your coins, they just haven't told you yet?